The Cohorts in the I4C

Cohort name

Tasmania Infant Health Survey (TIHS)

Cohort Country

Australia

Cohort Website

None

Cohort paper

Tikellis G, Dwyer T, Paltiel O, et al. The International Childhood Cancer Cohort Consortium (I4C): A research platform of prospective cohorts for studying the aetiology of childhood cancers. Paediatr Perinat Epidemiol. 2018 Nov;32(6):568-583. doi: 10.1111/ppe.12519.

Brown RC, Dwyer T, Kasten C, et al. Cohort profile: the International Childhood Cancer Cohort Consortium (I4C). Int J Epidemiol. 2007 Aug;36(4):724-30. doi: 10.1093/ije/dyl299. Epub 2007 Jan 25. PMID: 17255350.

Principal investigators name (I4C)

Professors Terence Dwyer & Anne-Louise Ponsonby

Principal investigators e-mail address (I4C)

terry.dwyer@mcri.edu.au

annelouise.ponsonby@florey.edu.au

Principal investigator(s) (I4C) institution address

Murdoch Children’s Research Institute, Royal Children's Hospital, 50 Flemington Rd, Parkville VIC 3052, Australia.

The Florey Institute of Neuroscience and Mental Health, 30 Royal Parade, Parkville VIC 3052, Australia.

Basic description

A large-scale study conducted in Tasmania, Australia, between 1987 and 1995.

Main aim of cohort

To investigate factors related to Sudden Infant Death Syndrome (SIDS)

Period of enrollment

January 1, 1988 -  December 31,1995

Inclusion period

12 months

Inclusion criteria

Singleton live births with no Down Syndrome, achieving a high score on ‘risk for SIDS’ screening

Exclusion criteria

None

Study population

10,627 

Source population

Tasmanian live births

Response rate

91%

Time points for follow-up

One month of age home visit, and three months of age telephone contact

Planned age of children at end of follow-up

One year of age.

Exposures

In the first week of life infants were measured for anthropometry and a questionnaire was administered to mothers on usual infant sleeping position and the infant sleeping environment as well as infant feeding and illnesses

Number of biological samples

Approx 3,000

Genotyping

none

Source of linkage determining diagnosis

Tasmanian Cancer Registry

Cancer cases (total)

51

Date of latest linkage

1995

Cohort Country

Denmark

Cohort Website

www.dnbc.dk

Cohort paper

Katrine Strandberg-Larsen, Luise Cederkvist, Anne Aakjær, Anne Ahrendt Bjerregaard, Nis Brix, Bjarke Feenstra, Inger Kristine Meder, Ellen A Nohr, Sjurdur F Olsen, Sandra Søgaard Tøttenborg, Cecilia Høst Ramlau-Hansen, Anne-Marie Vangsted, Anne-Marie Nybo Andersen, Cohort Profile: the Danish National Birth Cohort from foetal life to young adulthood, International Journal of Epidemiology, Volume 54, Issue 4, August 2025, dyaf083, https://doi.org/10.1093/ije/dyaf083

Principal investigators name (I4C)

Sjurdur F. Olsen

Principal investigators e-mail address (I4C)

sfo@ssi.dk

Principal investigator(s) (I4C) institution address

Statens Serum Institut

Basic description

Main aim of cohort

The main aim is to investigate the causal links between early-life exposures and the development of diseases later in life, with a strong focus on identifying opportunities for disease prevention.

Period of enrollment

1996 – 2002

Inclusion period

Typically during first antenatal visit (around 6–12 weeks of gestation).

Inclusion criteria

Pregnant women in Denmark who could speak Danish and were willing to participate

Exclusion criteria

No formal exclusion criteria

Study population

~97 000 children, 88 000 mothers.

Source population

National

Response rate

30 - 35 %

Time points for follow-up

Data collection during

Pregnancy (multiple times), infancy, and child’s age 7, 11, 14 and 18 years.

Children are followed from fetal life into young adulthood.

Planned age of children at end of follow-up

Throughout life.

Exposures

Maternal lifestyle, diet, environmental factors, occupational exposures, medication use, infections, and psychosocial stress during pregnancy. These exposures are assessed through structured telephone interviews, self-administered questionnaires, and biological samples collected from mothers during pregnancy and from children at birth. The cohort also integrates data from national health and social registries, allowing for long-term tracking of environmental, medical, and socioeconomic exposures throughout the life course.

Number of biological samples

600 000 samples, including blood samples from 1^st and 2^nd and cord blood at birth.

Genotyping

Approximately 100 000

Source of linkage determining diagnosis

Danish Childhood Cancer Registry

Cancer cases (total)

258 children with a total of 261 cancer diagnosis.

Three children have two cancer diagnoses.

Date of latest linkage

2022-12-31

Cohort name

Jerusalem Perinatal Study Cohort

Cohort Country

Israel

Cohort paper

Harlap S, Davies AM, Deutsch L, Calderon-Margalit R, Manor O, Paltiel O, Tiram E, Yanetz R, Perrin MC, Terry MB, Malaspina D, Friedlander Y. The Jerusalem Perinatal Study cohort, 1964-2005: methods and a review of the main results. Paediatr Perinat Epidemiol. 2007 May;21(3):256-73. doi: 10.1111/j.1365-3016.2007.00799.x. PMID: 17439536;

Lawrence GM, Siscovick DS, Calderon-Margalit R, Enquobahrie DA, Granot-Hershkovitz E, Harlap S, Manor O, Meiner V, Paltiel O, Kwok PY, Friedlander Y, Hochner H. Cohort Profile: The Jerusalem Perinatal Family Follow-Up Study. Int J Epidemiol. 2016 Apr;45(2):343-52. doi: 10.1093/ije/dyv120.. PMID: 26163255;

Principal investigators name (I4C)

Ora Paltiel

Principal investigators e-mail address (I4C)

Principal investigator(s) (I4C) institution address

Braun School of Public Health and Community Medicine

Hadassah-Hebrew University,  POB 12000 Jerusalem Israel  9112001

Basic description

All offspring born to West Jerusalem mothers 1964-1976, their mothers and fathers. Complete birth information, parental demographics, birth complications, congenital anomalies. Partial data on hospitalizations in first five years of life, adolescent height and weight for 60-70%, linkage to cancer and death registries

Main aim of cohort

To assess perinatal and developmental  risk factors for adult diseases

Period of enrollment

1964-1976

Inclusion criteria

All births and stillbirths to mothers who were residents of West Jerusalem during the study period

Exclusion criteria

none

Study population

All births-unselected

Source population

West Jerusalem

Response rate

Close to 100% but some  perinatal data missing for smaller hospitals

Time points for follow-up

Age 17, 1999, 2005, 2016, 2024

Planned age of children at end of follow-up

Followed until adulthood

Exposures

Parental characteristics, birth weight and birth modality, pregnancy and obstetric complications. Drugs in pregnancy (some), infections in pregnancy (some)

Number of biological samples

1500

Genotyping

<10%

Source of linkage determining diagnosis

Israel National Cancer registry

Cancer cases (total)

To age 15 :173; after age 18 (until 2014)- 1800;  2021 linkage numbers pending – estimated 4000

Date of latest linkage

2021

Cohort Country

Norway

Cohort Website

https://www.fhi.no/en/ch/studies/moba/

Cohort paper

Cohort Profile Update: The Norwegian Mother, Father and Child Cohort (MoBa) - PubMed

Principal investigators name (I4C)

Per Magnus

Principal investigators e-mail address (I4C)

Per.Magnus@fhi.no

Principal investigator(s) (I4C) institution address

Norwegian Institute of Public health

Main aim of cohort

The main aim of MoBa is to detect causes of serious diseases through estimation of specific exposure-outcome associations among children and parents.  MoBa also contributes to the description of disease trajectories and comorbidities, to the analyses of factors that are associated with the progression of disease, on social determinants of health and on health as a determinant of educational, social and economic achievement. This is accomplished by assembling as much data as possible on exposures, mediators, effect-modifying variables, and outcomes.

Period of enrollment

01.06.1999 – 31.12.2008

Inclusion period

Before week 18 of pregnancy

Inclusion criteria

Pregnant women attending a routine ultrasound examination in 50 out of 52 hospitals in Norway.

Exclusion criteria

None, but a restriction was the ability to read Norwegian as all material was written in Norwegian alone. 

Study population

114 000 children, 95 000 mothers, and 75 000 fathers.

Source population

277 702 pregnant women were invited during the recruitment period

Response rate

41 %

Time points for follow-up

After birth, questionnaires were sent out when the child was 6 months, 18 months and 3, 5, 7 and 8 years old, the period 13-15 years, 14 years, and many more. The child answers their first questionnaire when 14 years old, then 16/17, 18, 19 and 20.

Planned age of children at end of follow-up

Continuing. Plans are being made for third-generation recruitment.  

Exposures

Exposures include toxic substances, nutrients, medications, psychological stressors, lifestyle habits, etc. based on questionnaires, measured in biological samples (blood, teeth, urine), or assessed through geo-coding

Number of biological samples

Pregnant women: 100 585 (Whole blood, plasma, DNA, urine)
Mother after birth: 87366 (Whole blood, plasma, DNA)
Father during pregnancy: 73521 (Whole blood, plasma, DNA)
Child: 93521 (Plasma, DNA, RNA from umbilical cord blood)
(Total samples 354 993)
Metabolomics, proteomics, methylations, telomeres, mitochondrial sequencing, and exome sequencing in subsamples

Genotyping

82 % of total study population

Source of linkage determining diagnosis

The Cancer registry of Norway

Cancer cases (total)

< 15 years:
≥ 15 years:  tba

Date of latest linkage

31.12.2021

Cohort name

ALSPAC – Avon Longitudinal Study of Parents and Children

Cohort Country

England

Cohort Website

https://www.bristol.ac.uk/alspac/

Cohort paper

G0 Mothers

G0 Partners

G1

G2

Principal investigators name (I4C)

Kate Northstone

Principal investigators e-mail address (I4C)

Kate.Northstone@bristol.ac.uk

Principal investigator(s) (I4C) institution address

University of Bristol

Main aim of cohort

The original aim of ALSPAC was to determine which biological, environmental, social, psychological and psychosocial factors are associated with the survival and optimal health and development of the fetus, infant and child, and the ways in which causal relationships might vary with the genetic composition of mother and/or child.

Period of enrollment

1990-1992

Inclusion period

 Pregnancy

Inclusion criteria

Pregnant women with due dates between 1^st April 1991 – 31^st December 1992 resident in the previous 3 health districts covering the city of Bristol in the South West of Bristol

Exclusion criteria

None

Study population

14,500 women, ~3000 partners and 13978 children (with ~2000 children of the children/pregnancies)

Source population

All pregnant women

Response rate

85% of the eligible population of pregnant women were enrolled

Time points for follow-up

Multiple timepoints in both parents and children up to the current age of ~33-34 via questionnaire, face to face visits (including collection of biological samples) and administrative linkage

Planned age of children at end of follow-up

No planned end currently

Exposures

Many exposures including toxic substances, nutrients, medications, psychological stressors, lifestyle habits, etc. based on questionnaires, measured in biological samples (blood, teeth, urine), or assessed through geo-coding

Number of biological samples

Multiple timepoints – dependent on time

Metabolomics, proteomics, exome sequencing in the majority, methylation in subsamples

Genotyping

Yes ~85%

Source of linkage determining diagnosis

UK Cancer registry – previously from the Office of National Statistics now from NHS England

Cancer cases (total)

<15:

≥ 15 years:  TBC

Date of latest linkage

2023 (linkages currently being updated with 2024 data)

Cohort Country

USA

Cohort paper

Klebanoff MA. The collaborative perinatal project: a 50-year retrospective. Paediatr Perinat Epidemiol. 2009 Jan;23(1):2–8. doi: 10.1111/j.1365-3016.2008.00984.x

Hardy JB. The Collaborative Perinatal Project: lessons and legacy. Annals of Epidemiology 2003;13:303-311.

Principal investigators name (I4C)

Mark A Klebanoff

Principal investigator(s) (I4C) institution address

Professor of Epidemiology Emeritus,

Ohio State University, Columbus, Ohio

Main aim of cohort

The  multisite Collaborative Perinatal Project (CPP) cohort study was designed to identify the effects of complications during either pregnancy or the perinatal period on birth and child outcomes, especially neurological disorders such as cerebral palsy. This is reflected in the original name of the project: “Collaborative Study of Cerebral Palsy, Mental Retardation, and Other Neurological and Sensory Disorders of Infants and Children.  The data were collected at 12 academic centers to facilitate expert involvement in the research and to complete follow up. A drawback was that the populations at each center were not representative of the U.S. population.  Key goals were to:  (1) Identify factors during pregnancy, labor, delivery, and the first year of life that might influence the development of conditions such as cerebral palsy, epilepsy, and intellectual disabilities. (2) Collect comprehensive data on maternal health, environmental exposures, medical care, and child development.

Period of enrollment

1959-1966

Inclusion period

As early in pregnancy as feasible -usually at their initial antenatal visit.

Inclusion criteria

Participants were recruited from 12 academic medical centers across the United States. Each center had its own sampling frames and aimed to enroll a representative sample of its local population. There were no specific exclusion based on health status, such as race, socioeconomic status, or pre-existing health conditions.  

The study focused on live singleton births. Women had to consent to participate in the study and agree to longitudinal follow-up of their children.

Exclusion criteria

Women were generally included unless they declined consent, enrolled too late in pregnancy, had multiple births, or were expected to be difficult to follow, such as those planning adoption.

Study population

~58.908 pregnancies, 54,390 births. 37, 431 children in follow-up 1^st year, and many through age 7-8 years.  

Source population

  Subjects were identified from all eligible pregnant women seen and cared for in obstetric/gynecologic departments of 12 academic medical centers across the United states.

Response rate

~68 % of the children born in the study were successfully followed for at least 1 year.

Time points for follow-up

Mothers: During pregnancy, at labor and delivery

Children: Neonatal period, 4 months, 8 months, 12 months, and 3, 4, 7 and 8 years of age.

Planned age of children at end of follow-up

8 years. The original study ended around 1974, but follow-up research has continued through substudies like the New England Family Study (NEFS), the NICHD Mortality Linkage Study, and epigenetic and aging research, each based on original study sites.

Exposures

Include Chronic conditions, reproductive history, pre-pregnancy metrics, Smoking, alcohol, diet, physical activity, Education, income, marital status, employment, Environmental Exposures: Residential and occupational hazards Prenatal care, labor details and medication use.

For the child exposures included Birth weight, gestational age, complications, Growth metrics, motor milestones, neurological exams, Cognitive tests, emotional and social assessments, Language milestones, hearing and speech evaluations, Home environment, caregiving, family structure, Illnesses, hospitalizations, immunizations, IQ, school readiness and learning assessments.

CPP collected Maternal Serum at each prenatal visit, placental samples, blood samples from mothers and children.  

Number of biological samples

198,389 serum samples from 46,000+ women

36,215 cord blood samples;

Proposals to use the samples should be submitted to the Biospecimen Repository Access and Data Sharing Committee of the National Institute of Child Health and Disease

.

Genotyping

Some samples, particularly from the subset collected by the NEFS involving around 17,000 participants, have been genotyped. An exact number is not publicly available.

Source of linkage determining diagnosis

<15: Original study: Clinical examinations; hospital documentation and clinical records, pathology reports and diagnostic imaging.

>15 Recent sub studies: Cases have been identified through the National Death Index, hospital and outpatient records, NEFS surveys and interviews, state registry linkages, and biological sample analysis.

Cancer cases (total)

<15: 51 Cases during the 7- 8 year follow-up. (17 leukemias, 8 central nervous system tumors, 6 neuroblastomas, 7 Wilms’ tumors, 5 lymphomas, 3 retinoblastomas, 5 other cancers)

>15: Unknown total

Date of latest linkage

<15: 1974 (likely)

>15: Mortality linkage study: 2017.  The last linkage with the U.S. National Death Index for mortality follow-up was through 2016. Follow-up studies in NEFS continues

Cohort Country

Japan

Cohort Website

https://www.env.go.jp/chemi/ceh/en/

Cohort paper

Michikawa T, Nitta H, Nakayama SF, Yamazaki S, Isobe T, Tamura K, Suda E, Ono M, Yonemoto J, Iwai-Shimada M, Kobayashi Y, Suzuki G, Kawamoto T; Japan Environment and Children’s Study Group.

Baseline Profile of Participants in the Japan Environment and Children’s Study (JECS).

J Epidemiol. 2018;28(2):99–104.

doi: 10.2188/jea.JE20170018

Link to full text: J-STAGE Article

Principal investigators name (I4C)

Michihiro Kamijima

Principal investigators e-mail address (I4C)

jecs-en@nies.go.jp

Principal investigator(s) (I4C) institution address

Nagoya City University Graduate School of Medical Sciences/

National Institute for Environmental Studies (NIES)

Basic description

Main aim of cohort

The goal of JECS is to identify and elucidate environmental factors that affect children's health and development. Taking the study results into account, Japanese government will develop effective strategies to manage such factors, including regulation of the use of substances that adversely affect health and development of children. The final goal is to create an environment that facilitates the healthy growth of children and enables parents to raise their children without unnecessary anxiety.

Period of enrollment

2011 - 2014

Inclusion period

2011 - 2014

Inclusion criteria

Pregnant women with expected delivery date between August 2011 and March 2014, lived in designated study areas, and visited cooperating healthcare providers or local government offices issuing Maternal and Child Health Handbook during pregnancy.

Exclusion criteria

Not providing informed consent, unable to understand the study procedures or complete questionnaires independently in Japanese or were expected to be unavailable at the time of delivery.

Study population

100 148 children, 95 248 mothers and 49 189 fathers

Source population

The source population of JECS comprised women residing in 15 regions (Hokkaido; Miyagi, Fukushima, Chiba, Kanagawa,

Koshin, Toyama, Aichi, Kyoto, Osaka, Hyogo, Tottori, Kochi, Fukuoka, and South Kyushu/Okinawa) across Japan who were eligible for recruitment between January 2011 and March 2014), counting approximately 230 000 eligible pregnancies.

Response rate

~45%

Time points for follow-up

Questionnaire administration, biological sample collections and medical record transcription were performed twice during pregnancy, at birth and one month after birth. After birth, questionnaires were sent out twice a year until child became 12 years. After 13 years, parents and child separately receive electronic questionnaires multiple times a year. Child undergoes physical and developmental examination at ages of 8 and 12.

Planned age of children at end of follow-up

When the oldest child becomes around 40 years old.

Exposures

Lifestyle and behaviour; Diet and nutrition; Environmental exposures (e.g., smoking, chemicals); Socioeconomic status; Mental health and stressor levels.

Includes information on medical records (prenatal care, birth outcomes, paediatric health assessments); environmental measurements (air and household chemical exposure); geographic and climate data

Number of biological samples

Mothers: blood, cord blood, breast milk, hair and urine samples during pregnancy and at birth.

Fathers: blood samples at birth/dependent on availability

Children: blood spot, hair, blood, urine, and teeth.

Genotyping

All mothers and fathers. All children whose cord blood is available. ~85-90% of total study population

Source of linkage determining diagnosis

Cancer cases (total)

<15 years: 127 cases in total (up to 8 years)

≥ 15 years: NA

Date of latest linkage

Cohort Country

Brazil

Cohort Website

www.boldrini.org.br

Principal investigators name (I4C)

Dra. Silvia Regina Brandalise

Principal investigators e-mail address (I4C)

silvia@boldrini.org.br

Principal investigator(s) (I4C) institution address

Boldrini Pediatric Oncology and Hematological Research Center

Basic description

The prospective cohort study of children born in Campinas, São Paulo, Brazil, aims to follow these children from pregnancy to eighteen years of age. The project includes the collection of biological samples, such as maternal blood, placenta, and umbilical cord blood at different stages of life, and the administration of questionnaires to pregnant women and during the first months of the child's life. Analysis of the collected data will include tests and statistical models to identify possible associations between environmental exposures and the occurrence of cancer or other diseases, such as congenital malformations and immunodeficiencies. The study also includes spatial analysis of the associations through georeferencing of events and mapping of risk factors in the studied area.

Main aim of cohort

Study risk factors for children's cancer

Period of enrollment

11-04-2016.-. until at the moment

Inclusion period

Pregnant women up to 14 weeks gestation

Inclusion criteria

Contacted pregnant women contacted who agreed to participate in the research

Exclusion criteria

Women with advanced pregnancies or who do not sign the Informed Consent Form

Study population

Pregnant women who receive prenatal care at Basic Health Units (UBS) of the Unified Health System (SUS)

Source population

23.250 pregnant women were contacted during the period

Response rate

85%

Time points for follow-up

An epidemiological questionnaire was administered during the first and third trimesters of pregnancy. And after birth, questionnaires are administered when the child is 6 months and 18 months of age.

Planned age of children at end of follow-up

18 years old

Exposures

Exposures include agrotoxic substances, alcohol, smoking, insecticide, radiation, heavy metals, medications, lifestyle habits, etc. based on information from questionnaires, detected in biological samples (blood, placenta) or assessed through geocoding.

Number of biological samples

Pregnant women: 115,824 (whole blood of pregnant women: plasma, serum, red blood cells, bufy coat)

Postpartum mothers: 9.687 (placenta, umbilical cord: plasma, red blood cells, buffy coat)

(Total samples: 125.511)

Genotyping

Does not apply

Source of linkage determining diagnosis

Boldrini Pediatric Oncology and Hematological Research Center

Cancer cases (total)

3 (three) cases in chindren, till now

Date of latest linkage

September 10^th , 2025

Cohort name

NINFEA - Nascita e INFanzia: gli Effetti dell’Ambiente

Cohort Country

Italy

Cohort Website

https://www.progettoninfea.it/

Cohort paper

Richiardi L, Baussano I, Vizzini L, Douwes J, Pearce N, Merletti F; NINFEA cohort. Feasibility of recruiting a birth cohort through the Internet: the experience of the NINFEA cohort. Eur J Epidemiol. 2007;22(12):831-7. doi: 10.1007/s10654-007-9194-2

Principal investigators name (I4C)

 Milena Maule

Principal investigators e-mail address (I4C)

 milena.maule@unito.it

Principal investigator(s) (I4C) institution address

Cancer Epidemiology Unit, Department of Medical Sciences, University of Turin, Via Santena 7, 10126, Turin, Italy

Basic description

The NINFEA (Nascita e Infanzia: gli Effetti dell’Ambiente) study is an Italian web-based birth cohort study investigating the impact of exposures from early life onwards on child health across their life course. Recruitment started in 2005 in the city of Turin and was then extended to the rest of Italy. Pregnant women were invited to enroll by completing a baseline questionnaire. Further follow-up information was obtained with additional online questionnaires completed by the mothers 6 and 18 months after delivery and when children turned 4, 7, 10, 13, 16, and by the participating young adults at 19 years of age. Between the 6 and 18 months follow-up, mothers were invited to provide saliva samples for themselves and their children. Saliva samples of young adults are being collected at 19 years of age.

Main aim of cohort

The study investigates the effect of several exposures (e.g., environmental, behavioural, socioeconomic) during pre-natal and post-natal life on health across the life course.

Period of enrollment

2005-2016

Inclusion period

2005-2016

Inclusion criteria

Members of the cohorts are children born to mothers who had access to the internet, enough knowledge of Italian to complete online questionnaires, and who volunteered to participate at any time during pregnancy.

Exclusion criteria

Mothers below 18 years of age at delivery and enrollment after delivery.

Study population

7641 pregnant women enrolled.

6825 children with 6-months follow up.

Source population

Pregnant women between 2005 and 2016 country-wide.

Response rate

Available at: https://www.progettoninfea.it/attachments/139

10, 13, 16 and 19-year follow-up are ongoing and response rates are updated yearly.

Time points for follow-up

6 and 18 months; 4, 7, 10, 13, 16, and 19 years of age.

Planned age of children at end of follow-up

Adulthood.

Exposures

Information was collected through online questionnaires on exposures before and during pregnancy and in the post-natal period.

Exposures include environmental factors including indoor environment, medical history, lifestyle and behavioural factors, based on questionnaires and geocoded addresses.

Number of biological samples

~3500 mother-child saliva samples were collected.

DNA methylation analysis was performed on 140 saliva samples of children residing in the Turin province (Illumina 450k). An additional 96 biological samples are currently under analysis.

Genotyping

No

Source of linkage determining diagnosis

Childhood Cancer Registry of Piedmont (65% of NINFEA participants are resident in the Piedmont region)

Mod.1.01 (Italian centralized hospital-based registry hosted by Italian Association for Pediatric Hematology Oncology) (35%of NINFEA participants are resident in other Italian regions).

Cancer cases (total)

 < 15 years: 11

Date of latest linkage

 October 2017 (planned update: 2025)

Cohort Country

Korea

Cohort Website

https://myr.ewha.ac.kr/ewhamedeng/research/ko-ches.do

Cohort profile

Cohort profile: Beyond birth cohort study - The Korean CHildren's ENvironmental health Study (Ko-CHENS)

Jeong KS, Kim S, Kim WJ, Kim HC, Bae J, Hong YC, Ha M, Ahn K, Lee JY, Kim Y, Ha E; Ko-CHENS Study group. Environ Res. 2019 May;172:358-366. doi: 10.1016/j.envres.2018.12.009. Epub 2018 Dec 14. PMID: 30825686.

Research papers

[1] Machine learning-based analysis on factors influencing blood heavy metal concentrations in the Korean CHildren's ENvironmental health Study (Ko-CHENS). Jung S, Shah S, Oh J, Bang Y, Lee JH, Kim HC, Jeong KS, Park H, Lee EK, Hong YC, Ha E; Ko-CHENS Study group. Sci Total Environ. 2025 May 25;978:179401. doi: 10.1016/j.scitotenv.2025.179401. Epub 2025 Apr 22.

[2] Sex-specific effects of prenatal exposure to phthalates and bisphenol A on adverse birth outcomes: Results from The Korean CHildren's ENvironmental health Study (Ko-CHENS). Oh J, Shah S, Lee KA, Park E, Lee DW, Hong YC, Song S, Kim SY, Park H, Kim HC, Jeong KS, Ha E; Ko-CHENS Study group. Environ Int. 2025 May;199:109518. doi: 10.1016/j.envint.2025.109518. Epub 2025 May 6.

[3] Pregnant women's lifestyles and exposure to endocrine-disrupting chemicals: A machine learning approach. Shah S, Oh J, Bang Y, Jung S, Kim HC, Jeong KS, Park MH, Lee KA, Ryoo JH, Kim YJ, Song S, Park H, Ha E; Ko-CHENS study group. Environ Pollut. 2025 Feb 1;366:125309. doi: 10.1016/j.envpol.2024.125309. Epub 2024 Nov 13.

[4] Effects of heavy metal exposure during pregnancy on birth outcomes. Sci Rep. Zinia SS, Yang KH, Lee EJ, Lim MN, Kim J, Kim WJ; Ko-CHENS Study group.  2023 Nov 3;13(1):18990. doi: 10.1038/s41598-023-46271-0.

[5] Ambient particulate matter and surrounding greenness in relation to sleep quality among pregnant women: A nationwide cohort study. Lamichhane DK, Ha E, Hong YC, Lee DW, Park MS, Song S, Kim S, Kim WJ, Bae J, Kim HC; Ko-CHENS Study Group. Heliyon. 2024 Feb 20;10(5):e26742. doi: 10.1016/j.heliyon.2024.e26742.

[6] Associations of Night Shift Status During Pregnancy With Small for Gestational Age and Preterm Births. J Korean Med Sci. Lee SJ, Kim C, Lee EJ, Lim MN, Na S, Kim WJ; Ko-CHENS Study Group. 2024 Jan 8;39(1):e25. doi: 10.3346/jkms.2024.39.e25.

[7] Association between phthalate exposure and sleep quality in pregnant women: Results from the Korean Children's Environmental Health Study with repeated assessment of exposure. Lamichhane DK, Ha E, Bakian AV, Hong YC, Lee DW, Park MS, Song S, Kim S, Park H, Kim WJ, Bae J, Kim HC. Environ Epidemiol. 2024 Aug 20;8(5):e329. doi: 10.1097/EE9.0000000000000329.

Principal investigators name (I4C)

Eunhee Ha

Principal investigators e-mail address (I4C)

eunheeha@ewha.ac.kr

Principal investigator(s) (I4C) institution address

EWHA Woman’s University, College of Medicine

Department of Occupational and Environmental Medicine

260, Gonghang-daero, Gangseo-gu, Seoul 07804, Republic of Korea

Basic description

Main aim of cohort

To investigate the impact of environmental exposures on children's health across their life course, starting from the prenatal period through adolescence, with follow-up until 2036

Period of enrollment

2015 – 2021. Participants were enrolled into a Core Cohort with more detailed data collection and a Main Cohort with larger sample size

Inclusion period

Early pregnancy, typically in the first trimester

Inclusion criteria

Pregnant women residing in South Korea, able and willing to provide informed consent and with access to participating medical institutions involved in the cohort study.

Exclusion criteria

Severe health conditions, multiple pregnancies, high-risk lifestyle behaviors, and participation in other conflicting clinical studies.

Study population

In total 70 000 mother-child pairs (approximately 140 000 individuals). Core Cohort; 5000 participants and Main cohort with 65 000 mothers and their children.   

Source population

Nationwide recruitment

Response rate

A total of 5,458 mother–child pairs participated in the Core Cohort. The follow-up rates at 6, 12, 24, and 36 months were 92.5% (n=5,051), 88.4% (n=4,804), 81.5% (n=4,449), and 82.3% (n=4,490), respectively.

Time points for follow-up

Infancy and Toddlerhood, Preschool Age, Elementary School Age, Middle School Age, High School Age

Planned age of children at end of follow-up

When the oldest child is 19 years old (2034 -2040)

Exposures

Environmental exposures: Chemical exposures (Endocrine-disrupting chemicals (EDCs) and Heavy metals (Pb, Hg, and Cd), Environmental and Physical Exposures (Outdoor air pollution, Indoor air quality, Greenness and urban environment, Noise pollution, Temperature and climate factors), Lifestyle and behavior; Maternal smoking and alcohol use, Dietary patterns, Occupational exposures (e.g., night shift work), Socioeconomic status and stress), and biological sampling (19 substances analyzed)

Number of biological samples

Approximately 5,000 (Core cohort) each of maternal blood and urine, cord blood, placenta, hair and nails, and child blood and urine at follow-up stages.

Genotyping

Biological samples will be stored in a biobank, allowing for genotyping analyses to be conducted in the future.

Source of linkage determining diagnosis

The Ko-CHENS data are linked with NHIS data. The NHIS database is established for national health insurance claims purposes and includes information on diagnoses and treatments.

Cancer cases (total)

Since the Ko-CHENS follows children born from 2015 onwards, it is still too early to comprehensively assess cancers in children and adolescents (ages 0–19). Among approximately 70,000 Ko-CHENS participants linked with NHIS data, only around 40 cases of pediatric cancer (ICD-10: C00–C97) were identified during the 2015–2021 period.

Date of latest linkage

For children, Ko-CHENS data are linked with NHIS information from 2015 to 2023, while for parents, data are available from 2012 to 2023. For parents, an additional 3 years of pre-pregnancy information is included to identify prior medical history. The most recent data linkage was performed in 2024, and updates will continue on an ongoing basis.

Cohort name

The Born in Guangzhou Cohort Study (BIGCS)

Cohort Country

China

Cohort Website

http://www.bigcs.com.cn/

Cohort paper

The Born in Guangzhou Cohort Study (BIGCS). Eur J Epidemiol

. 2017 Apr;32(4):337-346.

DOI: 10.1007/s10654-017-0239-x

Principal investigators name (I4C)

Xiu Qiu

Principal investigators e-mail address (I4C)

xiu.qiu@bigcs.org; qxiu0161@163.com

Principal investigator(s) (I4C) institution address

Division of Birth Cohort Study, Guangzhou Women and

Children’s Medical Center, Guangzhou Medical University,

9 Junsui Road, Zhujiang Newtown, Tianhe District,

Guangzhou 510623, China

Basic description

The Born in Guangzhou Cohort Study (BIGCS) is a large-scale prospective study and serves as a research platform for maternal and child health in southern China.

Main aim of cohort

The main aim of BIGCS is to investigate the impacts of social, biological and environmental influences on pregnancy and child health and development through comprehensive data and biological sample collection. Ultimately, BIGCS aims to generate valuable evidence to inform public health policies and strategies.

Period of enrollment

From 01.02.2012, continuing

Inclusion period

Before week 20 of pregnancy

Inclusion criteria

Pregnant women who reside in Guangzhou and who attend Guangzhou Women and Children’s Medical Center (GWCMC) for antenatal care and intend to deliver at GWCMC.

Exclusion criteria

None, but a restriction was the ability to complete questionnaires in Mandarin or Cantonese language.

Study population

62090 mothers, 59452 children, 9207 fathers, and 2366 grandmothers by June 2025

Source population

111767 pregnant women were invited during the recruitment period

Response rate

55.6%

Time points for follow-up

After enrolment, follow-ups are conducted during the mid- and late-pregnancy stages, at the time of delivery, and at the following time points for the offspring: 42 days, 6 months, 1 year, 3 years, 6 years, 9 years and 12 years (planned).

Planned age of children at end of follow-up

The plan is to follow the offspring up into adulthood.

Exposures

Exposures include lifestyle, nutritional status, environmental pollution, medical and family history, psychological and mental health, and genetics. These are assessed using questionnaires and biological samples (such as blood, placenta and stool) or linkage to other databases.

Number of biological samples

Pregnant women: 1092364(serum, plasma, buffy coat, DNA, stool, red blood cell, blood clot)

Father: 48201(serum, plasma, buffy coat, DNA, red blood cell, blood clot)

Child: 1328830 (serum, plasma, buffy coat, red blood cell, DNA from peripheral blood and umbilical cord blood, stool, placenta and cord)

Grandmothers: 18219 (serum, plasma, buffy coat, DNA, saliva, red blood cell)

(Total samples 2487614)

Genotyping

7.4% of total study population

Source of linkage determining diagnosis

Medical records from GWCMC and regional health platform.

Cancer cases (total)

Mothers: 1404

Children: 61

Date of latest linkage

10.9.2025

Cohort name

Generation Victoria (GenV)

Cohort Country

Australia

Cohort Website

https://www.genv.org.au/

Cohort Registration

https://clinicaltrials.gov/study/NCT05394363

Cohort paper

Cohort Profile: Generation Victoria (GenV)

Preprint: https://doi.org/10.1101/2025.08.21.25333171

Principal investigator’s name (I4C)

Melissa Wake

Principal investigators e-mail address (I4C)

melissa.wake@mcri.edu.au

Principal investigator(s) (I4C) institution address

Murdoch Children's Research Institute, The Royal Children's Hospital, 50 Flemington Road, Parkville, Victoria 3052 Australia

Basic description

Generation Victoria (GenV) is a whole-of-state longitudinal research platform established to improve child and adult health, development and wellbeing through discovery and interventional research. It currently includes over 120,000 participants (around 50,000 children and 70,000 adults – their parents) and comprises participant-provided and service-collected data and biosamples, with planned 5-6 yearly child and parent phenotypic waves.

Main aim of cohort

GenV’s Vision is of a healthier population by 2035 through prediction, prevention and timely responses to complex problems - starting with children and pre-midlife adults.

GenV’s Mission is to create the world’s first whole-population longitudinal testbed – a statewide discovery, intervention and simulation platform – to deliver preventive solutions for communities, priority groups, Australia and globally.

Period of enrollment

Ongoing – Victorian individuals in the birth window and their parents can join at any age.

Inclusion period

From birth onwards.

Inclusion criteria

All children living in Victoria, Australia, and born 2021-Oct-04 and 2023-Oct-03, and their parents/guardians, are eligible for GenV’s ‘Cohort 2020s’.

Exclusion criteria

None.

Study population

Total to date: 123,738 participants (49,783 children, 48,213 birth mothers/parents, 25,428 fathers, 314 other parents/guardians)

Comprises:

- Cohort 2020s (main statewide GenV cohort): 108,773 participants (43,945 children, 42,550 birth mothers/parents, 21,988 fathers, 290 other parents/guardians)

- Advance Cohort: 14,965 participants (5,838 children, 5,663 birth mothers/parents, 3,440 fathers, 24 other parents/guardians).

Source population

147,813 eligible child births for the establishment (newborn) phase of GenV’s ‘Cohort 2020s’ – source population will evolve with migration/death

Response rate

~30% of eligible child births for GenV’s ‘Cohort 2020s’

Time points for follow-up

Participant-provided data and biosamples at recruitment. Universal data and biosample linkage ongoing. Major phenotypic waves around ages 6, 11, and 16. Supplemented by optional depth biosamples and brief digital surveys offered quarterly to age 12 months, then 6 monthly to age 5 years.

Planned age of children at end of follow-up

Continuing; consent is for inclusion throughout life and after death, unless withdraws.

Exposures

Focus is on universal cell-to-society universal exposome throughout life and retrospectively as far back as is feasible for children and parents. Will include:

- whole-population services and other administrative linked data;

- clinical data;

- extensive temporo-spatial exposures (eg policies, environment, viral patterns, antibiotic use);

- lifestyle, feeding/nutrition, medicine/supplements, psychosocial stressors;

- biological (genetic, molecular, toxins etc).

Number of biological samples

Biosamples already collected (round figures):

Saliva = 100,400 (from 39,000 birth mothers/parents, 39,100 children, 22,300 fathers and other parents/guardians)

Newborn blood spot (NBS) = 40,000

Infant stool (age 7 days) = 7,200

Longitudinal infant stool (age 2 years) = 3,500

Breast Milk = 6,500

Pregnancy plasma = 16,500

Pregnancy serum = 31,800

Pregnancy Group B Streptococcus (GBS) elution = 5,200

Biosamples under consideration for Early School phenotypic wave (child age 6-7y) with strong cancer relevance:

Capillary blood, shed teeth (children only), skin tape stripping, saliva

Genotyping

Yes – once funding secured.

Source of linkage determining diagnosis

Not yet commenced. We hope for future linkage with:

- Victorian Cancer Registry

- Cancer-specific registries (eg melanoma, breast, paediatric, colorectal).

Cancer cases (total)

Unknown. Broad estimates from age-related child & adult incidence:

·        2021-2040: n= ~4,000

·        2041-2050: n= ~5,500

·        2051-2060: n= ~10,000

·        …

·        Combined lifespan: n= 62,500

Date of latest linkage

Latest linkage to state-based administrative datasets: September 2025.

Linkage to cancer registry: not commenced.